New Bounds for Zagreb Eccentricity Indices

Nilanjan De

Department of Basic Science and Humanities (Mathematics), Calcutta Institute of Engineering and Management, Kolkata, India.

DOI: 10.4236/ojdm.2013.31014                

Abstract

The Zagrebeccentricity indices are the eccentricity version of the classical Zagrebindices. The first Zagrebeccentricity index (E₁(G)) is defined as sum of squares of the eccentricities of the vertices and the second Zagrebeccentricity index (E₂(G)) is equal to sum of product of the eccentricities of the adjacent vertices. In this paper we give some new upper and lower bounds for first and second Zagreb eccentricity indices.

Keywords

Vertex Degree; Eccentricity; Zagreb Eccentricity Indices

Conflicts of Interest

The authors declare no conflicts of interest.

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